Do As I SaY! Programmatic Access Control with Explicit Identities

Abstract

We address the programmatic realization of the access control model of security in distributed systems. Our aim is to bridge the gap between abstract/declarative policies and their concrete/operational implementations. We present a programming formalism (which extends the asynchronous pi-calculus with explicit principals) and a specification logic (which extends Datalog with primitives from authorization logic). We provide two kinds of static analysis methods to tie implementation to specification. Type checking determines that a program is a sound implementation of policy; i.e., that all granted accesses are safe in the face of arbitrary opponents. Model checking determines a degree of completeness; i.e., that accesses permitted by the policy are actually granted in the implementation.